Table 3 Summary of previous studies of caffeine effects during submaximal exercise
From: Low doses of caffeine reduce heart rate during submaximal cycle ergometry
Study | Caffeine use | Caffeine | % of VO2max | Mode | Effects of caffeine on HR | Systolic Blood Pressure | |
|---|---|---|---|---|---|---|---|
A | Bangsbo (1992) | n = 11 not reported | 500 mg | 80–100 | Treadmill | No diff | Not studied |
B | Bell (1998) | n = 8 habitual | 5 mg/kg | 85 | Cycle | ↑ at 5 min; not at 10 min | Not studied |
C | Bell (2002) | n = 8 non-habitual n = 13 habitual | 5 mg/kg | 50 & 80 | Cycle | No diff at 50% ↑ at 80% for both h + nh | Not studied |
D | Bell et al (2003) | n = 9 habitual | 5 mg/kg | 80 | Cycle | No diff | Not studied |
E | Casal et al (1985) | n = 9 not reported | 6 mg/kg | 75 | Treadmill | No diff | Not studied |
F | Daniels et al (1998) | n = 10 non-habitual | 6 mg/kg | 65 | Cycle | No diff | Higher with caffeine |
G | Engels et al (1999) | n = 8 habitual | 5 mg/kg | 30 | Cycle | No diff | Higher with caffeine |
H | Flinn et al (1990) | n = 9 non-habitual | 10 mg/kg | 40–100 | Cycle | No diff | Not studied |
I | French et al (1991) | n = 6 non-habitual | 10 mg/kg | 75 | Treadmill | No diff | Not studied |
J | Gaesser GA (1985) | n = 8 habitual | 5 mg/kg | 37–100 | Cycle | ↓ at 37–77% max, no diff at max | Not studied |
K | Graham et al (2000) | n = 9 non-habitual | 6 mg/kg | 70 | Cycle | No diff | Higher with caffeine |
L | Jacobsen et al (2001) | n = 8 non-habitual | 6 mg/kg | 70 | Cycle | No diff | Not studied |
M | Kaminsky (1998) | n = 8 non-habitual n = 8 habitual | 5 kg/mg | 30, 50, 70 | Treadmill | No diff | Higher for both groups with caffeine |
N | McNaughton (1987) | n = 10 non-habitual | 10 + 15 mg/kg | Not reported | Cycle | ↑ Higher with caffeine | Not studied |
O | Nishijima (2002) | n = 8 habitual | 300 mg | 40–50 | Cycle | Not measured | No diff |
P | Perkins R (1975) | n = 14 not reported | 4 + 7 + 10 mg/kg | 50–100 | Cycle | No diff for any doses | Not studied |
Q | Powers (1983) | n = 7 not reported | 5 mg/kg | 25 – 100 | Cycle | No diff | Not studied |
R | Sasaki (1987) | n = 7 not reported | 3.2 mg/kg | 63 | Treadmill | ↑ Higher with caffeine | Not studied |
S | Sullivan et al (1992) | n = 5 non-habitual n = 5 habitual | 3.3 mg/kg | 45 | Treadmill | ↓ for non-habitual No diff for habitual | Higher for both groups with caffeine |
T | Sung et al (1990) | n = 34 habitual | 5 mg/kg | 25 & 50 | Cycle | No diff | Higher with caffeine |
U | Sung et al (1995) | n = 12 habitual | 3.3 mg/kg | Not reported | Cycle | No diff | Higher with caffeine |
V | Tarnopolosky (1989) | n = 6 habitual | 6 mg/kg | 70 | Treadmill | No diff | Not studied |
W | Trice et al (1993) | n = 8 habitual | 5 mg/kg | 85–90 | Cycle | No diff | Not studied |
X | Turley & Gerst (2006) | n = 52 not reported | 5 mg/kg | 65% of max hr 75% of max hr | Cycle | ↓ for boys & girls at 65% ↓ for boys & girls at 75% | ↑ for boys at 65% ↓ for girls at 75% |
Y | Weir et al (1987) | n = 6 not reported | 6.5 mg/kg | 72–76 | Treadmill | No diff | Not studied |
McClaran (present study) | n = 9 non-habitual | 1.5 + 3 mg/kg | 30, 46, 63 | Cycle | ↓ at 30-63% max | No diff | |